Sharpening apparatus for shears and scissors



y 1964 T. P. BENTON 3,131,518

SHARPENING APPARATUS FOR SHEARS AND SCISSORS Filed Feb. 26, 1962 INVENTOR. Tom 5A2 2 BENTON United States Patent Generally speaking, the present invention comprises sharpening apparatus which may be employed for sharpening shears and scissors of various types including lawn shears and desk scissors, although not specifically so limited.

The apparatus is so arranged as to guide the positioning of each blade of a pair of shears or scissors (one at a time) into the correct angular relationship relative to an abrasive surface so that manual reciprocation of said blade relative to said abrasive surface for a few strokes will effectively sharpen the blade in an optimum manner whereby to restore the shears or scissors to a fully and completely sharpened condition equal to, or superior to, the initial condition of the shears or scissors when first manufactured.

The abrasive surface used for sharpening each blade of a pair of shears or scissors is effectively shiftable after it has been used for a period of time such that its abrasive efliciency has been impaired, and is adapted to be replaced by a fresh, previously unused, abrasive surface having a maximum abrasive efiiciency. In one preferred form of the invention, this is accomplished by employing an abrasively coated strip of thin-sheet material which can be controllably fed toward a sharpening zone or region in a manner effectively replacing another portion thereof which has been previously positioned in said sharpening region or zone and has been previously used to an extent such as to impair its sharpening efiiciency. Said previously used portion of the strip may be effectively severed and removed from the remainder thereof and thrown away. This provides an arrangement whereby the device can at all times be kept within an optimum abrasive efficiency range.

These two important features of the present inventionthe correctly guided positioning of a blade to be sharpened with respect to the abrasive surface and the controllable replacement of the abrasive surface in an extremely easy manner, effectively cooperate to produce a virtually foolproof, easy-to-operate sharpener for shears or scissors which is vastly superior to conventional prior art sharpeners frequently used for this purpose and which, in many cases, do not correctly predetermine the sharpening angle in the advantageous manner of the present invention, thus requiring that such a sharpening operation be conducted by a skilled person, and which, in many cases, also do not provide meansfor effectively changing the abrasive surface, thus requiring that a used abrasive surface be frequently cleaned if it is to be abrasively efficient.

It is an object of the present invention to provide an improved apparatus for sharpening shears and scissors blades (or, for that matter, any blade which requires a predetermined sharpening angle for maximum efficiency) of the general character referred to above and embodying any or all of the various specific aspects thereof referred to above, and which is of extremely simple, in expensive easy-to-use, and substantially foolproof construction such as to be conducive to wide-spread use thereof.

Further objects are implicit in the detailed description which follows hereinafter (which is to be considered as exemplary of, but not specifically limiting, the invention) and said objects will be apparent to persons skilled in the art after a careful study of the detailed description which follows hereinafter.

For the purpose of clarifying the nature of the present invention, one exemplary embodiment is illustrated in the hereinbelow-described figures of the accompanying single drawing sheet and is described in detail hereinafter.

FIG. 1 is a perspective view illustrating one exemplary embodiment of the present invention in an operative use position. Indeed, one blade of a pair of scissors is shown in sharpening position relative to the apparatus and the double headed arrow indicates the direction of reciprocation thereof during a sharpening operation. Since the pair of scissors (or shears) comprises no part of the present invention, it is shown in phantom in FIG. 1.

FIG. 2 is a view, partly in section and partly in elevation, taken along the plane and in the direction of the arrows 22 of FIG. 3.

FIG. 3 is a view, partly in elevation and partly in section, taken along the plane and in the direction of the arrows 33 of FIG. 2.

FIG. 4 is an elevational view as seen from the left end of the complete device in FIG. 1 or FIG. 2.

FIG. 5 is a fragmentary elevational view of the outwardly projecting platform extension member carrying the abrasively coated strip of thin-sheet material and of the roller means on the back side thereof which effectively comprises used-strip-removal means for use in removing an extended used and abrasively inefficient piece of the abrasively coated strip of thin-sheet material. In other words, it is an enlargement of the top central portion of FIG. 2. However, FIG. 5 shows the cross-section of a typical blade in phantom in a sharpening position, whereas FIG. 2 does not show said blade.

Referring to the figures for exemplary purposes, one illustrative embodiment of the invention takes a typical exemplary form wherein it comprises a body member, indicated generally at 10, which may be made of plastic, metal, or any other suitable material, and which has a contact face portion 11, which in the example illustrated comprises a metal plate having an edge flange fastened in place by the fastening screws 12, although the invention is not specifically so limited.

The body member 10 is also effectively provided with an outwardly angularly projecting platform extension member 13 positioned in a plane lying at a predetermined angle with respect to the contact face portion 11, said predetermined angle corresponding to and being an optimum angle for sharpening a blade (such as each of the blades of a pair of scissors or shears, or any other blade having an angular edge).

In the specific example illustrated, the outwardly projecting platform extension member 13 has a base plate portion 14 which is fastened by suitable fastening screws (or equivalent fastening means) 15 to a face portion 16 of the body member 10 which is spaced from an opposite face portion 17 of the body member If) whereby to define therebetween an exit slot means, indicated generally at 18, to allow the egress of a free end portion 1a of an abrasively coated strip of thin-sheet material which is carried in the form of a spiral roll 26.

The spiral roll 20 of the abrasively coated strip of thinsheet material is carried by a mounting and dispensing spindle means, indicated generally at 21, within a hollow chamber 22 in the body member 10. This is best shown in FIGS. 2 and 3.

The mounting and dispensing spindle means 21 in the specific form illustrated, comprises a shaft 23 carrying a sleeve 24 which has the inner end 25 of the spiral roll 29 of the abrasively coated strip of thin-sheet material fastened thereto by way of an entry slot 26 which allows said inner end to pass inwardly through the sleeve 24 into a position adjacent to the shaft 23.

The free end 19 of the abrasively coated strip of thinsheet material then passes out through the first horizontal exit slot portion 18A and then through the upwardly and angularly inclined exit slot portion 18B into a position such that the exterior abrasively coated surface thereof, indicated at 27, is outwardly carried by an operative surface (in this case, the left surface as seen in FIG. 2) of the platform extension member 13 in an exteriorly exposed manner. Said free end 19 of the abrasively coated strip of thin-sheet material then passes around the outer end of the platform extension member 13 and downwardly or toward the body member 16 along the opposite inoperative surface (in this case, the right surface as seen in FIG. 2) of the platform member 13 for engagement by the roller means 28 which effectively comprises usedstrip-removal means, indicated generally at 2 and adapted for use in effectively shifting the entire free end 19 of the abrasively coated strip of thin-sheet material outwardly and then removing the used and abrasively ineificient portion from the end thereof.

In connection with the above, it should be noted that normally the abrasively-coated exterior portion 27 of the strip of thin-sheet material which lies on the operative surface of the platform extension member 13 will be abrasively efficient for a number of blade-sharpening operations of the general type indicated in FIG. 1 and FIG. wherein a blade, such as that indicated in broken lines at St in said figures, is reciprocated in the directions of the double-headed arrow indicated at 31 in FIG. 1 until the angular edge 32- of the blade 3f) is fully sharpened at the predetermined proper angle. Then the other blade is similarly sharpened. After a number of blade-sharpening operations, the abrasively coated surface 27 of the free end 19 of the strip of thin-sheet material may become abrasively inefficient through wear of the abrasive particles and through clogging of the surface of the abrasive strip with the metal abraded from the blade edge 32. When this situation prevails, the tip 33 of the free end 19 of the abrasively coated strip of thin-sheet material is then digitally grasped and pulled so as to cause its extension around the roller means 18 until a fresh abrasive surface 27 of said free end 19 lies along the outwardly projecting operative surface of the platform extension member 13. At this time the previously used and abrasively inefficient outermost portion of the free end 1% of the abrasively coated strip of thin-sheet material, which has been extended beyond the roller means 28, can be laterally torn off or sheared off and thrown away. It should be noted that in certain forms of the invention, shearing means may be provided at this location for facilitating the shearing off of said previously used, abrasively ineflicient outermost portion of the free end 19 of the abrasively coate' strip of thin-sheet material.

During the above-described extending operation of the free end 19 of the abrasively coated thin-sheet of materrial, no excess thereof is supplied from the spiral roll 29 thereof carried by the spindle means 21 because said spindle means 21 is provided with controllably adjustable back-tensioning means, indicated generally at 34, which, in the specific example illustrated, comprises the threaded nut 35 mounted on a threaded portion 36 at one end of the shaft 23 and which abuts a washer 37 lying in and forcibly abutting a recess 38 in the body member at one side thereof. The opposite end of the shaft 23 is similarly threaded at 39 and carries a nut 40 abutting a washer 44 which abuts the opposite surface of the body member 10. The arrangement is such that the effective frictional engagement may be adjusted by tightening the nut so as to provide a desired degree of back tensioning to the free end 19 of the abrasively coated strip of thin-sheet material.

It should be noted that the back-tensioning means 34 is exemplary only and the invention contemplates the use of various other equivalent arrangements.

It should also be noted that the roller means 28 is effectively fastened to the body member 10 by arms 41 on each side thereof which are fastened to said body member if) by fastening screws 42, or the like. This provides an arrangement where said arms 41 are on each side of the angularly projecting platform extension member 13 and are also on each side of the free end 19 of the abrasively coated strip of thin-sheet material whereby to effectively comprise keeper means indicated generally at 43 for said free end 19 of said abrasively coated strip of thin-sheet material which acts to keep it in the proper relationship with respect to the platform extension member 13. This is also facilitated by the roller means 28 which effectively holds said free end 19 near the outermost portion thereof against the back or inoperative surface of the platform extension member 13;

It should be noted that the words operative and inoperative, as used herein with respect to the front and rear surfaces of the platform extension member 13, refer entirely to the blade sharpening operation.

It should be understood that the figures and the specific description thereof set forth in the application are for the purpose of illustrating the present invention and are not to be construed as limting the present invention to the precise and detailed specific structure shown in the figures and specifically described hereinbefore. Rather, the real invention is intended to include substantially equivalent constructions embodying the basic teachings and inventive concept of the present invention.

I claim:

1. Blade sharpening apparatus comprising: a body member having a contact face portion provided adjacent thereto with an outwardly projecting platform extension member positioned in a plane lying at a predetermined angle with respect to said contact face portion, said angle corresponding to and being an optimum angle for sharp ening a blade, said outwardly projecting platform extension member being provided with interchangeable abrasive surface means comprising a longitudinal strip of flexible thin-sheet material provided on one surface thereof with an abrasive coating, said abrasively coated strip of thin-sheet material being in the form of a spiral roll having a free end extending outwardly over an operative surface of said platform extension member and then rear- Wardly along an opposite inoperative surface of said platform extension member to a used-strip-removal region; and mounting and dispensing spindle means rotatively mounted with respect to said body member and rotatively effectively dispensably mounting said spiral roll of said strip of abrasively coated flexible thin-sheet material for controlled dispensing thereof whereby to replace a used surface thereof lying over said operative surface of said platform extension member with a fresh unused portion of said abrasively coated strip of thin-sheet material.

2. Apparatus as defined in claim 1, wherein said rota tively mounted dispensing spindle means is provided with back-tensioning means whereby to impart back tension to the free end of said abrasively coated strip of flexible thin-sheet mate-rial.

3. Apparatus as defined in claim 1, including usedstrip-removal rneans carried by the body member in said used-strip-removal region and adapted for effective use in removing a used portion of the abrasively coated strip of flexible thin-sheet material which has been manually moved into said used-stripaemoval region by the application of force thereto.

4. Apparatus as defined in claim 1, including usedstrip-removal means carried by the body member in said used-strip-removal region and adapted for effective use in removing a used portion of the abrasive-ly coated strip of flexible thin-sheet material which has been manually moved into said used-strip-removal region by the application of force thereto, said used-strip-removal means cornprising roller means abutting one surface of a used portion of said abrasively coated strip of flexible thin-sheet material and forcing the other surface thereof against said opposite inoperative surface of said platform extension member whereby said used portion of said strip of thin-sheet material is constrained in a manner such that the digital application of transverse shearing force to the end of said unused portion will effectively shear it off while the remainder of the abnasively coated flexible strip of thin-sheet material remains held in operative relationship with respect to said platform extension member.

5. Apparatus as defined in claim 1, including keeper means adapted to etfectively position the abrasively coated flexible strip of thin-sheet material in the proper relationship on said platform extension member and to prevent it from lateral displacement relative thereto.

6. Apparatus as defined in claim 1, including keeper means adapted to eifectively position the abrasively coated flexible strip of thin-sheet material in the proper relationship on said platform extension member and to prevent it from lateral displacement relative thereto, said keeper means comprising mounting arms effectively mounting said roller means with respect to said body member and in a position adjacent to said opposite inoperative surface of said platform extension member.

6 7. Apparatus as defined in claim 1, wherein said mounting and dispensing spindle means is rotatively mounted Within said body member and wherein said body member is provided with exit slot means communicating said rotatively mounted dispensing spindle means with said operative surtace of said platform extension member.

References Cited in the file of this patent UNITED STATES PATENTS 413,786 Miller Oct. 29, 1889 492,810 King Mar. 7, 1893 525,916 Merriman Sept. 11, 1894 1,025,859 Oalahan May 7, 1912 1,748,313 Steuber Feb. 25, 1930 2,232,149 'Iautz ..Feb. 18, 1941 2,408,815 Stonard Oct. 8, 1946 2,832,179 Beltram Apr. 29, 1958 2,853,837 Lamison Sept. 30, 1958 2,924,047 M-achovec Feb. 9, 1960 FOREIGN PATENTS 137,773 Great Britain Jan. 22, 1920 721,019 Finance Dec. 12, 1931 

1. BLADE SHARPENING APPARATUS COMPRISING: A BODY MEMBER HAVING A CONTACT FACE PORTION PROVIDED ADJACENT THERETO WITH AN OUTWARDLY PROJECTING PLATFORM EXTENSION MEMBER POSITIONED IN A PLANE LYING AT A PREDETERMINED ANGLE WITH RESPECT TO SAID CONTACT FACE PORTION, SAID ANGLE CORRESPONDING TO AND BEING AN OPTIMUM ANGLE FOR SHARPENING A BLADE, SAID OUTWARDLY PROJECTING PLATFORM EXTENSION MEMBER BEING PROVIDED WITH INTERCHANGEABLE ABRASIVE SURFACE MEANS COMPRISING A LONGITUDINAL STRIP OF FLEXIBLE THIN-SHEET MATERIAL PROVIDED ON ONE SURFACE THEREOF WITH AN ABRASIVE COATING, SAID ABRASIVELY COATED STRIP OF THIN-SHEET MATERIAL BEING IN THE FORM OF A SPIRAL ROLL HAVING A FREE END EXTENDING OUTWARDLY OVER AN OPERATIVE SURFACE OF SAID PLATFORM EXTENSION MEMBER AND THEN REARWARDLY ALONG AN OPPOSITE INOPERATIVE SURFACE OF SAID PLATFORM EXTENSION MEMBER TO A USED-STRIP-REMOVAL REGION; AND MOUNTING AND DISPENSING SPINDLE MEANS ROTATIVELY MOUNTED WITH RESPECT TO SAID BODY MEMBER AND ROTATIVELY EFFECTIVELY DISPENSABLY MOUNTING SAID SPIRAL ROLL OF SAID STRIP OF ABRASIVELY COATED FLEXIBLE THIN-SHEET MATERIAL FOR CONTROLLED DISPENSING THEREOF WHEREBY TO REPLACE A USED SURFACE THEREOF LYING OVER SAID OPERATIVE SURFACE OF SAID PLATFORM EXTENSION MEMBER WITH A FRESH UNUSED PORTION OF SAID ABRASIVELY COATED STRIP OF THIN-SHEET MATERIAL. 